package com.hong.fy_common_commomutil.common.utils;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

public class IpUtil {
    private static final String UNKNOWN = "unknown";
    private static final String LOCALHOST = "127.0.0.1";
    private static final String SEPARATOR = ",";

    public static String getIpAddr(HttpServletRequest request) {
        System.out.println(request);
        String ipAddress;
        try {
            ipAddress = request.getHeader("x-forwarded-for"); // 判断是否是反向代理
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) { // 如果是反向代理，则通过x-forwarded-for来获取客户端ip
                ipAddress = request.getHeader("Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getHeader("WL-Proxy-Client-IP");
            }
            if (ipAddress == null || ipAddress.length() == 0 || UNKNOWN.equalsIgnoreCase(ipAddress)) {
                ipAddress = request.getRemoteAddr(); // 没有代理，则直接获取客户端ip
                if (LOCALHOST.equals(ipAddress)) { // 如果是本地地址，则获取本地ip
                    InetAddress inet = null; // 根据网卡取本机配置的IP
                    try {
                        inet = InetAddress.getLocalHost(); // 取得本地的IP地址
                    } catch (UnknownHostException e) {
                        e.printStackTrace();
                    }
                    ipAddress = inet.getHostAddress(); // 得到本地IP地址
                }
            }
            // 对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
            // "***.***.***.***".length()
            if (ipAddress != null && ipAddress.length() >15) { // 判断是否为多IP
                if (ipAddress.indexOf(SEPARATOR) >0) {
                    ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
                }
            }
        } catch (Exception e) {
            ipAddress = "";
        }
        return ipAddress;
    }
}
